This invention relates to permanently installed irrigation systems and more specifically to underground, permanently installed irrigation systems for the irrigation and planting of landscape and flower beds that conserve water which decreases labor requirements for the installation of the flower bed.
The goal of any installed landscape and flowerbed irrigation system is to irrigate the target landscape plants as efficiently as is possible with minimum labor and parts, and therefore, the lowest installed cost possible. If these requirements are met, the water required to irrigate the landscape and flowerbed plants is conserved and the cost of installing the landscape/flower bed irrigation system is minimized. Current state of the irrigation systems for landscape/flower beds can be broken into three broad categories; sprinklers, drip and flood irrigation.
One of the earliest forms of irrigation is the flood irrigation concept. This type of irrigation requires that the flowerbed area to be irrigated be manipulated and contoured such that the water will flow into all of the required areas to be irrigated without leaving the intended area before the water has had sufficient time to soak into the surface soil. This requires labor intensive berming of the perimeter of the landscape/flower bed area and a source of water emission contained within the bermed perimeter. The benefits of this type of landscape/flower bed irrigation are low initial cost of the irrigation system with regard to materials and ease of installation. The drawbacks of this form of flood irrigation for a landscape/flower bed is inefficiency due to evaporation as the water sits on the surface of the bed and excessive loss of water due to deep percolation past the root zone of the plantings in the landscape/flower bed. Another drawback of the conventional landscape/flower bed with a flood irrigation system is the high level of labor required in the excavating and planting of the bed. The bed must have a berm completely around the perimeter and the landscape plants/flowers must be located at the proper depth. Also, for a healthy flowerbed it is often necessary to dig down 12 to 18 inches and amend the soil to provide suitable growing conditions for the plantings. For landscape and flower plants the soil must be of a texture to allow for water and air to be available to the plant at all times. Still another drawback of flood irrigation for flower/landscape beds is that by definition the entire area of the bed is flooded, providing moisture for the weeds/weed seeds which exist in the flower/landscape bed base soil, promoting the growth of the weeds. This unintended weed growth increases the labor requirement for maintaining a well-kept flower landscape beds. The unintended weed growth can also result in increased chemical herbicide weed killer usage, which can result in increased chemical run-off and environmental damage. Altogether, flood irrigation has been low on efficiency and high in labor requirements for landscape/flower beds installation of the bed and irrigation system.
The second form of irrigation to be discussed, sprinkler irrigation, is by far the most commonly used form of irrigation for landscape/flower beds. This form of irrigation utilized in flower/landscape beds consists of pipes located underground with shrub risers with spray nozzles threaded on them, referred to as fixed spray risers, or pop up spray head or sprinkler devices which pop up and then retract underground in between irrigation events. The spray nozzles affixed to either fixed risers or pop up risers spray out water in a pattern, which sprays out over the entire flower bed/landscape area. Due to the irregular shape and varying width of flower/landscape beds, it is often impossible to target spray head water only on the intended flower/landscape bed without significant over spray into unintended areas. Also, the distribution of water from these sprinkler devices is often interrupted in flower/landscape beds due to the height of the plantings in these areas creating irregular wetting patterns. Sprinkler irrigation in flower/landscape beds suffers from inefficiencies found in sprinkler irrigation of turf areas, namely high evaporation losses from being thrown in the air and evaporation from collecting on the leaf area material. In addition to the inherent distribution inefficiencies of broadcasting water through the air, sprinkler irrigation also suffers from the basic inefficiency of attempting to irrigate the entire flower/landscape bed while the planting area may only cover as little as 50 percent of the bed. In addition to irrigating the entire area automatically cutting the efficiency, the moisture not irrigating the bedding plants will irrigate weeds and weed seeds in the landscape bed soil, increasing again the need for herbicide chemicals. In all, sprinkler irrigation for flower/landscape beds, while being the most widely used form of irrigation, falls short of efficiency and is labor intensive and complicated to install and design.
The third form of prior art irrigation system is know as drip irrigation. Drip irrigation for flower/landscape beds comes in two installation methodologies, subsurface and surface drip irrigation. First for subsurface drip irrigation, a drip emitter line is buried six to twelve inches below the flower/landscape bed with the lines being twelve to eighteen inches apart. The emitters emit water at a rate from 0.5 to 2 gallons per hour and are subsurface drip emitter layout grid is to water the soil beneath the flower/landscape bed completely. The grid results in subsurface watering, but is subject to several limitations and inefficiencies. The physics of water movement through various textures of soil can act to limit the efficiency of subsurface drip irrigation. In a coarse soil, such as sand, the water moves outward and upward due to capillary action, but to a greater extent once the soil is saturated the water moves downward due to gravity force. This basic form of movement happens in all soil types, to the greatest extent in sand and to a lesser extent in a clay soil. As water drops below the drip line grid, which is already six to eight inches deep, it passes out of the root zone of flower/landscape plants. In addition to dropping below the root zone of the plantings, the fact that the grid irrigates the entire bed area, where the plantings may only occupy 50 percent of the bed area, the efficiency of the water placement is reduced. Placing the drip line below the bed surface creates several maintenance considerations, such as roots growing into the many individual, low flow emitter devices, cutting of the multiple emitter lines from shovels and maintenance tools, and plugging of the small emitter orifices with soil and sediment. The prevention of roots growing into the emitters can be accomplished by impregnating the plastic, which the emitters are molded out of with a chemical herbicide such as Treflan. To prevent damage from tools and shovels the lines must be buried as deep as possible, however this just makes the problem of water loss below the root zone greater. In addition to efficiency and maintenance concerns, there is also the increased labor requirements of installing the subsurface system.
In a modification of subsurface drip, U.S. Pat. No. 5,921,711, issued to Jonas Sipaila, entitled Subsurface Fluid Distribution Apparatus and Method, teaches a drainage and irrigation system based upon an unpressurized half pipe contained within a chamber filled with a significant depth of washed sand material. In this patent, it teaches excavation down to a required depth, laying of a liner, placement of a water channel, non-pressurized pipe, and filling with a washed sand material of significant depth (13 inches) to provide a growing root zone for the planted plant material. While this patent method does provide a controlled root zone, it is very expensive to provide the excavation and material for the root zone growth. Also, the method suffers from being the most labor intensive of all types of flower/landscape bed installation, requiring complete excavation to a significant depth and total replacement of the root zone growth material. Another limitation of this type of system is that it must be installed perfectly flat and in a descending order if more than one unit is installed in a serial manner. So that in addition to all of the additional labor requirements, there is extensive grading and leveling requirements. This system attempts to improve efficiency but does so at great expense in cost of labor and materials. It markedly increases the time required to establish a flower/landscape bed.
The next form of drip irrigation for flower/landscape beds is surface drip irrigation. In this form of drip irrigation, the drip emitters are located on the surface of the flower/landscape bed, typically with an emitter for each plant. This form of irrigation does provide increased efficiency due to watering at the plants only but is extremely sensitive to disturbance on the surface by tools and maintenance activities. This type of drip irrigation is the most utilized form of drip irrigation. The small molded and extruded plastic components of this form of irrigation are easily destroyed by normal gardening activities such as raking and digging, removing weeds, planting new flower/landscape beds, etc. Another danger is that because of the small diameter tubing and emitters that the point emission devices get moved away from the intended watering areas, increasing inefficiency in the irrigation system. While the surface drip irrigation system is not as labor intensive as the flood, sprinkler and subsurface drip irrigation systems to install, it is still fairly design and labor intensive to calculate the proper flow rate for each emitter/planting combination and the properly layout the entire system.
In a recent irrigation system for the irrigation of turf grass invented by the inventor of the current invention, U.S. Pat. No. 6,161,776 entitled Subsurface Mat Amendment System and Apparatus was developed to provide a simpler irrigation system specifically for the irrigation of turf grass. This system can be classified as a form of subsurface irrigation but because it is a continuous product intended for turf, it is not efficient for the irrigation of flower/landscape plantings.
Aside from the labor requirement of installing whatever form of irrigation system is selected for the flower/landscape bed, there is a significant element of labor required in the preparation of the flowerbed itself. Typical steps required to establish a flower/landscape bed in a typical turf grass lawn include: laying out the shape of the area, removing the turf grass, weeds and stones to a depth of 12 inches, bringing whatever soil amendments might be required for the soil base material, incorporating the amendments or tilling the soil to give a friable, open mixture of soil, creating border for the flower/landscape bed to prevent invasive turf grass and weeds from penetrating the bed, applying a weed killer to kill any weed or grass left in the bed, and then finally smoothing out the final surface of the bed. Once all of these tasks are completed, then the form of irrigation system can be installed to provide moisture to the plants within the bed.
All in all, no one prior art irrigation system for flower/landscape beds has been developed which is cost effective, easy to install, efficient and significantly reduces the labor requirement of installing irrigated flower/landscape beds, while also reducing the labor requirement of the actual preparation of the flower/landscape bed itself.